1. Field of Invention
The invention relates to electrical plugs and more particularly to such a waterproof plug and adaptor combination having a pair of electrical sockets for electrically connecting to prongs of another plugs and a waterproof transformer in which the plug and adaptor combination can be used as a charger.
2. Description of Related Art
Conventionally, an electrical plug is used to connect to, for example, a wall outlet for supplying AC power to an electrical device. Further, multifunctional plugs are commercially available. Such plug typically has a pair of sockets or other features.
U.S. Pat. No. 7,140,920 discloses an electric plug having two rear prong-receiving grooves so that the prongs of another plug may be electrically connected thereto by inserting into the grooves. The electric plug % has a voltage-limiting component.
Both U.S. application Ser. Nos. 12/081,017 and 12/244,361 are my previous endeavors. It is understood that waterproof feature is essential to plugs for outdoor applications. Further, outgrowth of a patent is always desired by inventors. Thus, the invention is directed to an improvement of the above applications.